Manitowoc QC0700, Technician'S Handbook

Page: 165 / 292

Part Number 80-1230-9 10/10 165
MOTOR SPEED SENSOR
QF0400/QC0700/QF0800/QF2200/QF2300
FUNCTION
The motor speed sensor verifies that the gearbox
motor is rotating at the correct speed.
FAILURE MODES
Motor Speed Sensor Open or Disconnected
(Ice machine will not start.)
Performs initial start-up procedure. Ten to 15 seconds
after the ice machine enters Water Flush (1), the ice
machine will initiate an Automatic Shut-Off cycle, flash
the Speed light and remain off for 60 minutes. (Refer
to “Gear Motor Speed” for additional information.)
Motor Speed Sensor Closed or Shorted
(Ice machine will not start.)
Performs initial start-up procedure. Ten to 15 seconds
after the ice machine enters Water Flush (1), the ice
machine will initiate an Automatic Shut-Off cycle, flash
the Speed light and remain off for 60 minutes. (Refer
to “Gear Motor Speed” for additional information.)
CHECK PROCEDURE
1. Allow time for the evaporator to warm.
Disconnecting power in the Freeze cycle will
result in ice build-up between the evaporator and
auger.
2. Verify the motor speed sensor is in place and
securely attached to the motor.
3. Verify the gearmotor run capacitor is functional.
4. Place toggle switch in the OFF position and place
an identifying mark on the evaporator/gearbox
coupling. This will provide a reference point to
verify the coupler is rotating.
5. Move the toggle switch to the ICE position and
verify the motor shaft and coupling are turning,
then observe the Speed light. (If the gear motor
and coupling will not rotate, the switch is
operating correctly.)